#region Licence
// Copyright (c) 2008 James Gregory (james@jagregory.com)
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
// 
//     * Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//     * Neither the name of James Gregory nor the names of its
//     contributors may be used to endorse or promote products derived from this
//     software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#endregion

using System;
using System.Collections.Generic;
using Boo.Lang.Compiler.TypeSystem;
using JAGregory.BooPlugin.Language.Members;

namespace JAGregory.BooPlugin.Language.Reflection
{
    internal class MemberDeclarationReflectionCache
    {
        private readonly Dictionary<EntityType, Type> typeMap = new Dictionary<EntityType, Type>();
        private bool alreadyCached;

        public Type FindMemberDeclarationType(EntityType entityType)
        {
            EnsureCache();

            return (typeMap.ContainsKey(entityType)) ? typeMap[entityType] : null;
        }

        private void EnsureCache()
        {
            if (alreadyCached) return;

            List<Type> types = new List<Type>(typeof(MemberDeclaration).Assembly.GetTypes());

            foreach (Type type in types)
            {
                object[] attributes = type.GetCustomAttributes(typeof(EntityTypeAttribute), false);

                if (attributes.Length > 0)
                    typeMap.Add(((EntityTypeAttribute)attributes[0]).EntityType, type);
            }

            alreadyCached = true;
        }
    }
}